Obesity is one of the fastest growing health problems in the world. For example, the Center for Disease Control estimates that over 20% of the U.S. population is obese. Gastric bypass surgery has been found to be one of the most effective treatments for morbid obesity.
Several different gastric bypass surgeries exist. The most common gastric bypass surgery is a Roux-en-Y gastric bypass. In a Roux-en-Y gastric bypass, the stomach is made smaller by creating a small pouch at the top of the stomach using surgical staples. The smaller stomach is connected to the middle portion of the small intestine (jejunum), bypassing the rest of the stomach and the upper portion of the small intestine (duodenum). The procedure can be done by making a large incision in the abdomen (an open procedure) or by making a small incision and using small instruments and a camera to guide the surgery (a laparoscopic procedure). Laparoscopic procedures generally result in quicker recoveries and shorter hospital stays. The risk associated with wound infection is significantly reduced and patients generally report less pain and experience a quicker return to normal activity.
When performing Roux-en-Y gastric bypass surgery laparoscopically, a number of conventional trocar devices are placed in various locations through the abdominal wall to provide passages through which surgical instruments, grasping devices and cameras may be inserted. As indicated above, such procedure involves the creation of a small stomach pouch and the attachment of the jejunum thereto by means of an anastomosis (commonly referred to as the G-J anastomosis). The jejunum portion is then reattached to the middle portion of the jejunum by another anastomosis (commonly referred to as the J-J anastomosis). Such arrangement therefore bypasses the severed portion of stomach and duodenum.
The circular stapler is an essential tool for construction of gastrointestinal anastomosis. Circular staplers useful for performing such procedures are disclosed, for example, in U.S. Pat. Nos. 5,104,025; 5,205,459; 5,285,945; and 5,309,927. In general, a conventional circular stapler typically consists of an elongated shaft that has a proximal actuating mechanism and a distal stapling mechanism mounted to the elongated shaft. The distal stapling mechanism commonly consists of a fixed stapling cartridge that contains a plurality of staples configured in a concentric circular array. A round cutting knife is concentrically mounted in the cartridge interior to the staples for axial travel therein. Extending axially from the center of the cartridge is a movable trocar shaft that is adapted to have a staple anvil removably coupled thereto. The anvil is configured to form the ends of the staples as they are driven into it. The distance between a distal face of the staple cartridge and the staple anvil is commonly controlled by an adjustment mechanism that is mounted to the proximal end of the stapler shaft for controlling the axial movement of the trocar. Tissue that is clamped between the staple cartridge and the staple anvil is simultaneously stapled and cut when the actuating mechanism is activated by the surgeon.
When using conventional circular staplers to perform Roux-en-Y gastric bypass surgery, the anvil of the device is placed transabdominally through an enlarged port site and passed through a gastrotomy on the anterior aspect of the stomach. The gastric pouch is constructed around the anvil and the gastrotomy is closed. The staple head of the circular stapler is inserted through the upper portion of the jejunum portion and the anvil is connected thereto. The stapler is then “fired” to create the anastomosis. Such method has been adopted by many surgeons. However, some drawbacks exist, including the need to enlarge the trocar site to accommodate the anvil and the construction of the gastrotomy and its closure. Such additional steps undesirably lengthen the time needed to complete the surgical procedure.
Thus, the need exists for a circular stapling device with an anvil arrangement that can puncture through gastric walls in an unexpanded state and then moved to an expanded state to facilitate formation of the anastomosis when the surgical stapler is actuated.
Such circular stapling devices are also commonly employed to removed diseased portions of the colon. Introduction and management of the circular stapler anvil into a conventional laparoscopic approach for colorectal surgery has been an ongoing limiter to employing laparoscopic procedures and techniques to complete such procedure. For example, laparoscopic colorectal procedures may be generally cumbersome to perform due to the number of steps involved. Such procedures are also complicated by the need to avoid crossing staple lines. Other problems that may be encountered with such procedures involve seeding from subject tissue removal, the need to create one or more ports for the introduction of anvils into the body cavity and the creation of colon defects that result from anvil placement challenges.
Thus, another need exists for a circular stapling device with an anvil arrangement that can be inserted into the patient in a collapsed state and then reconfigured into an expanded state to facilitate formation of the anastomosis when the surgical stapler is actuated.
The foregoing discussion is intended only to illustrate some of the shortcomings present in the field of the invention at the time, and should not be taken as a disavowal of claim scope.